U.S. Pat. No. 5,740,575 discloses a ramp kit comprising modular components that can be assembled to form ramp systems. The ramp kit includes a stand having support rails which extend between corresponding support posts, the rails being height adjustable to support an inclined ramp surface at a particular position along its length. However, the ramp system disclosed in this US patent has a number of significant limitations. Firstly, the support stand is relatively bulky, making it difficult to transport the components which are required to form a ramp system. Secondly, the range of height adjustment is quite limited and thirdly, height adjustment of each stand is reasonably time consuming as it involves alignment of holes formed in each end of two support rails with holes of support posts for subsequent insertion of two locating bolts.
Australian Patent Nos. 577,569 and 589,013 disclose modular component ramp kits having threaded support posts which are height adjustable to support an inclined ramp surface at a particular position along its length. Height adjustment is provided by threadable movement of a support nut along the length of the threaded support post. However, the ramp systems disclosed in these Australian patents appear to be quite cumbersome and costly to manufacture. Furthermore, their stability may be less than desirable in certain applications.